davis



(Model.)

T. D. DAVIS. KNOB ATTACHMENT.

No. 461,975. Patented 001;. 27, 1891,.

@mm1/momo me/wko@ UNITED STATES PATENT OFFICE.

THEODORE D. DAVIS, OF SYRACUSE, NEXV YORK, ASSIGNOR TO JULIA Il'.

DAVIS, OF SAME PLACE.

KNOB ATTACHMENT.

SPECIFICATION forming part of Letters Patent No. 461,975, dated October27', 1891.

Application iiled June 22, 1891. Serial No. 397,120% (Model.)

To @ZZ whom it may con/cern.-

Be it known that I, THEODORE D. DAVIS, a citizen of the United States,residing at Syracuse, in the county of Onondaga and State of New York,have invented certain new and useful Improvements in Knob Attachments toDoor Locks and Latches, of which the fol- 1lowing is a specification.

My invention relates to door knobs and latches; and it consists incertain improved parts and combination of parts whereby abetter and moredesirable device can be produced at less cost.

The best methods in which I have contemplated embodying my invention areillustrated in the accompanying drawings, and my said invention isdisclosed in the following description and claims.

In the said drawings, Figure l is an axial section of a door latch orlock embodying one form of my invention. Fig. 2 is a section of a knobtaken transversely of the spindle and through lugs of the socketengaging the knobs. Fig. 3 is a perspective view of'the thimble. Fig. 4is a transverse sectional View of the socket on line no Fig. l. Fig. 5is a perspective view of the nut. Fig. 6 is a transverse sectional viewof a modiied form of the saine. Fig.7 is a View of a modified form ofspindle and the device for securing the same, the locking device beingomitted. Figs. 8, 9, and l0 illustrate another modification of the sameparts.

In the drawings, A designates the door, B the lock or latch, and C thehub of the latch. The sockets G are preferably made of castiron,tapering on the outside, and provided with lugs K, which are adapted toenter recesses in the knobsEE. These lugs are preferably made in theform shown in section in Fig. 2, and are enlarged between their ends andare designed to engage straight-walled recesses, so that when forcedinto the recesses of wooden or like knobs the bers of the wood willhaveto yield slightly to permit the enlargement to pass. The tendency of thefibers compressed in doing this is to return to their normal position,and by so doing will make the union of the knob and socket very secure.In order to give the sockets an exterior finish,

I provide a thimble of brass or other line metal that can be highlypolished. This construction effects a considerable reduction in thecostof manufacture over a solid socket of iine metal, the appearancebeing the same. In casting the sockets it is impossible to secure aperfect uniformity of size, owing to the shrinkage of the metal and alsoto the rapping upon the pattern when loosening it from the sand of themold. In order to secure the piaci-ng of the thimble securely upon thesocket with the least expense, I give the socket and thimble each apeculiar construction. The socket near or adjacent to the knob is madeof a plain. cylindrical forrn. The opposite end, which is constructed toabut against the hub of the latch C. is also cylindrical for slightlymore than the distance which it enters the door, and between these twocylindrical portions the socket is ribbed or corrugated, as shown inFig. at. The thimble and socket may be cylindrical or of even diameterthroughout, but best results can be secured by constructing themslightly tapering, increasing in size outwardly. The interior of thethimble is for the greater portion of its length of a plain surface toengage with the ribs or corrugations of the socket, but the outer end ofthe spindle is interiorly corrugated, as shown in Fig. 3. This portionof the thimble engages the plain cylindricalpon tion of the socket nearthe knob, and the ridges or ribs which engage therewith are providedwith spaces at each side which permit these ribs to Hatten out andexpand on each side when the thimble is forced on the socket and avoidspreliminary fitting. The part of the thimble which engages thecorrugated portion of the socket is of such thickness that if it tightlyengages the ribs it will'yield by springing down between the ribs, whichaccomplishes the same result in respect to these portions of these twodevices. The portion of the thimble engaging theinner cylindricalportion of the socket is chamfered or tapered to a thin edge, so that itcan be easily compressed or upset on this portion of the socket if thesocket should be smaller than the interior of the thimble at that point,and readily yield if it is larger. The sockets, as are sectional view,Fig. 6.

seen, abut against the hub of the latch and they are secured in placeand in rigid contact with the same, pressing iirmly against it by thefollowing instrumentaiities:

The spindle D is of polygonal form, as usual, and is provided at one endwith a head and at its opposite end with a rounded portionscrew-threaded. The sockets of both knobs have an opening therethroughof a polygonal form loosely fitting the spindle. One of the knobs isprovided with a circular aperture. The securing device for the spindiepasses through this aperture and engages the end of the spindle. In Fig.l this securing device is a nut, which is elongated sufficiently toprovide for an adjustment of the parts to suit the thickness of lthevarious forms of latches, so that the sockets will in each case bepressed firmly against the hub of the latch. This nut is most clearlyshown in Fig. 5. This nut in this instance is shown as having the head aand the threaded portion b, the two parts being connected by a hollow orskeleton portion, which is the preferred form, as it can be cheaplyTmade by casting in the same manner as most of the other parts of thedevice. The threaded portion of the nut is provided with teeth orcorrugations, and the outer end of the socket is also provided withteeth or corrugations, and a spiral spring which acts as a pawl toengage with these teeth is placed on the spindle between them. The nutturns freely in the knob to draw the sockets together upon the hub C,and the spring-pawl retains thenut when once seated from reversemovement and prevents the loosening of the parts. While the spring-pawlis strong enough to keep the parts in proper relation when onceconnected, by applying a screw-driver to the nut it can be forced in thedirection to unscrew it against the force of the spring, bending ordistorting it, so as to release the parts.

The preferred construction of the body of the skeleton nut is shown inthe transverse In this view the hollow body of the nut is eXteriorly ofa true cylindrical form with a portion of the walls removed, the partremoved from the walls of the hollow portion being taken away at oneside. This is done in order that the nut may be made of the leastpossible amount of metal and yet have the required strength. It alsoenables me to use a nut of very small diameter, retaining all theeffective qualities of other forms of these nuts.l This constructionalso enables me to employ only a small opening through the knob, whichis very desirable.

In Fig. 7 I havel shown an equivalent or y 'modified construction inwhich I employ a screw in place of the nut, the female screw or threadsin this instance being in the spindle and the male on the fasteningdevice. In this instance I have shown the teeth or corrugations on thehead of the screw and those for engaging the opposite end of the springon the spindle.

In Figs. 8, 9, and 10 I show a screw for securing the spindle corrugatedlongitudinally. Then this is employed, I employ a lockingpiecesuch asshown in Fig. lO, which rests within the circular` opening in the knobin' the relation to thescrew shown in- Fig. 9, which is a sectionthrough a knob having the screw shown in Fig. 8 passing therethrough. Onreversing the screw to withdraw it a rib of the screw engages thelocking-piece and forces its opposite end against the wall of theaperture in the knob holding against reverse movement, unlessconsiderable force is applied to the screw through a screw-driver. Thespring-pawl and the device shown in Fig. l0 I term locking devices.7

In order that the thimbles may be securely held when once forced intoposition on the socket, I construct the thimbles with spurs I, which arebent over the end of the socket.

It will be understood that other devices may be employed in place of thespring; but

for certainty of operation and cheapness I prefer it to any otherconstruction I have contemplated'.

It will be seen that the thimbles are of a size to pass through theapertures in the roses, and that I adjust the spindle and knobs upon thehub of the latch and not upon the door. The securing device for thespindle is in every instance removable from the knob without disturbingor removing other parts and rotates freely within it in placing it inposition and in removing it.

Vhat I claim, and desire to secure by Letters Patent, is-

l. The combination, substantially as before set forth, with a latch, ofa knob and socket, a spindle having screw-threads, a retaining devicefor said spindle having screw-threads to engage those of the spindle andprovided with teeth or corrugations, a coiled spring to engage saidteeth or corrugations,-and means for engaging and holding the oppositeend of said pawl.

2. The combination, with a door-latch one of the spindle-sockets ofwhich is provided with teeth or corrugations, of a spindle having athreaded portion, a nut having teeth or corrugations, and a spring-pawlfor engaging the teeth or corrugations of both nut and socket,substantially as described.

3. In a latch, the combination, with a knob, of a socket having a rigidbody provided with ribs or a corrugated outer bearing-surface, a thimbleof softer metal having a plain interior surface for engaging the ribs ofthe socket and adapted to be forced upon the socket by a movementparallel with said ribs or corrngations, substantially as described.

4. In a latch, the combination, with a knob, of a socket havinga plaincylindrical portion adjacent to the knob and a thimble of softermaterial having its end adjacent to said knob lOO IIO

interiorly corrugated to engage the cylindrical portion of lthesocket,substantially as described.

5. In a latch, the combination,with a knob, of a socket having a portionof its outer surface ribbed or corrugated and a plain cylindricalsurface next adjacent to the knob, and a thimble of softer materialhaving a plain interior surface to engage the ribbed portion of thesocket, and a corrugated surface to engage the plain cylindrical portionof the socket, substantially as described.

6. In a latch, the combination, with a socket having knob-engaging lugs,said lugs being enlarged between their ends, of a Wooden knob havingstraight-Walled recesses to receive said lugs, substantially asdescribed.

7. The combination, With the socket of a latch, of a thimble of softermetal adapted to 2o be forced upon the socket by longitudinal movement,said thimble being provided with spurs for securing the thimble inplace, substantially as described.

8. In a door-latch, the combination,` with the latch, hub, and threadedspindle, of a socket abutting against thehub and provided 'with aprojection adapted to be forced into a THEODORE D. DAVIS.

Witnesses:

A. D. ALLEN, C. H. DAVIS.

